feat: bq datetime -> timestampfromparts (#3642)

sqlglot/dialects/bigquery.py

@@ -13,6 +13,7 @@
     date_add_interval_sql,
     datestrtodate_sql,
     build_formatted_time,
+    build_timestamp_from_parts,
     filter_array_using_unnest,
     if_sql,
     inline_array_unless_query,
@@ -322,6 +323,7 @@ class Parser(parser.Parser):
                 unit=exp.Literal.string(str(seq_get(args, 1))),
                 this=seq_get(args, 0),
             ),
+            "DATETIME": build_timestamp_from_parts,
             "DATETIME_ADD": build_date_delta_with_interval(exp.DatetimeAdd),
             "DATETIME_SUB": build_date_delta_with_interval(exp.DatetimeSub),
             "DIV": binary_from_function(exp.IntDiv),
@@ -648,6 +650,7 @@ class Generator(generator.Generator):
             ),
             exp.TimeAdd: date_add_interval_sql("TIME", "ADD"),
             exp.TimeFromParts: rename_func("TIME"),
+            exp.TimestampFromParts: rename_func("DATETIME"),
             exp.TimeSub: date_add_interval_sql("TIME", "SUB"),
             exp.TimestampAdd: date_add_interval_sql("TIMESTAMP", "ADD"),
             exp.TimestampDiff: rename_func("TIMESTAMP_DIFF"),

sqlglot/dialects/dialect.py

@@ -1192,5 +1192,14 @@ def _builder(dtype: exp.DataType) -> exp.DataType:
     return _builder
 
 
+def build_timestamp_from_parts(args: t.List) -> exp.Func:
+    if len(args) == 2:
+        # Other dialects don't have the TIMESTAMP_FROM_PARTS(date, time) concept,
+        # so we parse this into Anonymous for now instead of introducing complexity
+        return exp.Anonymous(this="TIMESTAMP_FROM_PARTS", expressions=args)
+
+    return exp.TimestampFromParts.from_arg_list(args)
+
+
 def sha256_sql(self: Generator, expression: exp.SHA2) -> str:
     return self.func(f"SHA{expression.text('length') or '256'}", expression.this)

sqlglot/dialects/snowflake.py

@@ -8,6 +8,7 @@
     NormalizationStrategy,
     binary_from_function,
     build_default_decimal_type,
+    build_timestamp_from_parts,
     date_delta_sql,
     date_trunc_to_time,
     datestrtodate_sql,
@@ -236,15 +237,6 @@ def _date_trunc_to_time(args: t.List) -> exp.DateTrunc | exp.TimestampTrunc:
     return trunc
 
 
-def _build_timestamp_from_parts(args: t.List) -> exp.Func:
-    if len(args) == 2:
-        # Other dialects don't have the TIMESTAMP_FROM_PARTS(date, time) concept,
-        # so we parse this into Anonymous for now instead of introducing complexity
-        return exp.Anonymous(this="TIMESTAMP_FROM_PARTS", expressions=args)
-
-    return exp.TimestampFromParts.from_arg_list(args)
-
-
 def _unqualify_unpivot_columns(expression: exp.Expression) -> exp.Expression:
     """
     Snowflake doesn't allow columns referenced in UNPIVOT to be qualified,
@@ -391,8 +383,8 @@ class Parser(parser.Parser):
             "TIMEDIFF": _build_datediff,
             "TIMESTAMPADD": _build_date_time_add(exp.DateAdd),
             "TIMESTAMPDIFF": _build_datediff,
-            "TIMESTAMPFROMPARTS": _build_timestamp_from_parts,
-            "TIMESTAMP_FROM_PARTS": _build_timestamp_from_parts,
+            "TIMESTAMPFROMPARTS": build_timestamp_from_parts,
+            "TIMESTAMP_FROM_PARTS": build_timestamp_from_parts,
             "TRY_TO_DATE": _build_datetime("TRY_TO_DATE", exp.DataType.Type.DATE, safe=True),
             "TO_DATE": _build_datetime("TO_DATE", exp.DataType.Type.DATE),
             "TO_NUMBER": lambda args: exp.ToNumber(

tests/dialects/test_bigquery.py

@@ -20,6 +20,14 @@ class TestBigQuery(Validator):
     maxDiff = None
 
     def test_bigquery(self):
+        self.validate_all(
+            "EXTRACT(HOUR FROM DATETIME(2008, 12, 25, 15, 30, 00))",
+            write={
+                "bigquery": "EXTRACT(HOUR FROM DATETIME(2008, 12, 25, 15, 30, 00))",
+                "duckdb": "EXTRACT(HOUR FROM MAKE_TIMESTAMP(2008, 12, 25, 15, 30, 00))",
+                "snowflake": "DATE_PART(HOUR, TIMESTAMP_FROM_PARTS(2008, 12, 25, 15, 30, 00))",
+            },
+        )
         self.validate_identity(
             """CREATE TEMPORARY FUNCTION FOO()
 RETURNS STRING